The present invention relates generally to a bicycle frame, and more particularly to a bicycle head bowl set having a stable structure which can be easily assembled.
As shown in FIG. 1, a prior art bicycle head bowl set 1 comprises a head tube 2, a front fork 3 put through the head tube 2 such that one end of the front fork is fitted with a handlebar support tube 4, a locking device 5 disposed at the top end of the front fork to press against the handlebar support tube 4, an upper bowl set 6, and a lower bowl set 7 which are respectively disposed at the top end and the bottom end of the head tube 2, and a tightening member 8 disposed between the front fork 3 and the bearing 601 of the upper bowl set 6 such that the tightening member 8 is pressed against by a cover member 602. In light of the tightening member 8 being annular in shape and having a notch, when the tightening member 8 is pressed against by the cover member 602, the tightening member 8 comes in intimate contact with the bearing 601 on one hand. On the other hand, the tightening member 8 and the front fork 3 are clamped securely together, thereby resulting in linkage of the front fork 3 and the inner edge of the bearing 601. As a result, the upper and the lower bowl sets 6 and 7 are fixed at a predetermined position.
In addition to the contact between the inner edge of the tightening member 8 and the front fork 3, the tapered portion 801 of the tightening member 8 is in contact with the tapered surface 603 of the bearing 601. In light of inadequate contact area, the locating effect of the entirety is poor. In the process of replacing the upper bowl set 6, the tightening member 8 must be separated from the bearing 601, thereby resulting in loss of component parts. In addition, the tapered surface 603 of the conventional bearing 601 is designed in various ways in terms of angle. As a result, the consumers are often troubled by the incompatibility of the tightening member 8 with the tapered surface 603 of the bearing 601 which is to be replaced due to damage.
It is the primary objective of the present invention to provide a bicycle and the like with a head bowl set which has an excellent structural stability.
It is another objective of the present invention to provide a bicycle and the like with a head bowl set which can be replaced and assembled with ease and speed.
The head bowl set of the present invention comprises a head tube, a front fork tube, a locking device, a lower bowl set, an upper bowl set, and a tightening member. The head tube is disposed at the front end of a bicycle frame. The front fork tube is put through the head tube to facilitate the connection of a front fork with a handlebar support tube. The locking device is disposed at the top end of the front fork tube and is formed of a head extending out of the front fork tube to press against the handlebar support tube. The lower bowl set comprises a cover member fitted at the outside of the front fork tube, and a carrying ring disposed at the bottom end of the head tube. There is a gap between the cover member and the carrying ring to accommodate a bearing. The upper bowl set comprises a cover member fitted at the outside of the front fork tube such that the cover member is pressed against by the handlebar tube, and a carrying ring disposed at the top end of the head tube. There is a gap between the cover member and the carrying ring to accommodate a bearing. The bearing is provided at the top end of the inner edge thereof with a tapered surface. The tightening member is annular in shape and is provided with a notch, a tapered portion corresponding to the tapered surface of the upper bowl set bearing, a straight wall extending downward from the tapered portion such that the straight wall is parallel to the inner edge of the bearing, and a hooked portion disposed at the bottom end of the straight wall such that the hooked portion is capable of catching the bottom edge of the bearing. The inner edge of the tightening member is in contact with the outer edge of the front fork tube. As a result, the head bowl set has advantages in design in that its structure is stable, and that its assembly is easy.